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          .globl   main
main:                                 # object1 = new object(); 
          li       $v0,9              #   allocate 32 bytes
          li       $a0,32             #  
          syscall                     #   $v0 = address
          sw       $v0,object1        #

          . . . . . .

object1:  .word    0
object2:  .word    0

The code allocates memory for the object and saves its address.

Initializing the Object

Next, the newly allocated memory must be initialized (in an object-oriented language this would be done by the object constructor). Here, again, is the layout of the object:

byte 0- 3: address of print()         # jump table
byte 4- 7: address of read()
byte 8-31: null terminated string     # 24 bytes (fixed size)

Here is the code that initializes the object. Register $v0 contains the address of the object.

          la       $t0,       #   initialize jump table
          sw       $t0,0($v0)        #   
          la       $t0,       #
          sw       $t0,4($v0)        #

          . . . 
read:                                # to be defined later

print:                               # to be defined later

Assume that the entry point for the read() is given by symbolic address read, and that the entry point for the print() is given by symbolic address print.


Fill in the blanks.